Here's one: (x + 1) (x - 1) = x² - 1
Another one: x³ / x(x²) = 1
How about (x² + 6x - 17)⁰ = 1
Or triggily: sin²(x) + cos²(x) = 1
An equation that is true for every value is known as an identity. Examples include a + b = b + a and sin 2 ( x ) + cos 2 ( x ) = 1 , which hold true for all applicable values. Such equations are useful in mathematical proofs and simplifications.
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